Numerical study of a fragile three-dimensional kinetically constrained model

TL;DR

This study numerically analyzes a three-dimensional kinetically constrained model, revealing its ability to quantitatively replicate experimental observations across various timescales in glassy systems.

Contribution

It introduces the NEF model as a 3D generalization of the East model and demonstrates its quantitative agreement with experimental data.

Findings

NEF model accurately describes relaxation timescales

Quantitative fit to optical Kerr effect data

Consistent with dielectric spectroscopy near glass transition

Abstract

We numerically study the three-dimensional generalization of the kinetically constrained East model, the North-or-East-or-Front (NEF) model. We characterize the equilibrium behaviour of the NEF model in detail, measuring the temperature dependence of several quantities: alpha-relaxation time, distributions of relaxation times, dynamic susceptibility, dynamic correlation length, and four-point susceptibility. We show that the NEF model describes quantitatively experimental observations over an exceptionally wide range of timescales. We illustrate this by fitting experimental data obtained both in the mildly supercooled regime by optical Kerr effect, and close to the glass transition by dielectric spectroscopy.